A randomized 'N-of-1' single blinded clinical trial of barbed dermal sutures vs. smooth sutures in elective plastic surgery shows differences in scar appearance two-years post-operatively.

BACKGROUND: Barbed sutures have unidirectional circumferential shallow barbs, which distribute tension throughout the wound and close wound securely without the need to tie knots. OBJECTIVES: We compare two different methods of wound closure in elective plastic surgical cases: barbed 3/0 V-Loc™180 suture and smooth 3/0 Maxon™ sutures, both polyglyconate monofilament synthetic absorbable sutures. We assessed the aesthetic long-term results with a minimum two year follow up. METHODS: This is a prospective, randomized controlled study with internal control. A single surgeon performed all cases. Patients who underwent elective operations that involved long wound closure were enrolled in the study. Each patient acted as their own internal control with half their wound being sutured with 3/0 V-Loc™180 barbed suture and the other half with smooth 3/0 Maxon™ deep dermal sutures and then a subcuticular skin closure. In both groups, the superficial fascial system was closed with 1 Vicryl interrupted sutures on both sides. Long-term cosmesis was evaluated using the modified Hollander cosmesis score by review of standardized postoperative photographs by 9 blinded plastic surgeons and specialist registrars. RESULTS: The study reports on 33 female patients. The time taken for wound closure was significantly reduced using the barbed suture (p < 0.001). There was no difference in the complication ratio in either group. Two-year aesthetic outcome was significantly superior when using the barbed suture (p = 0.0075). CONCLUSION: Barbed sutures closure of long wounds is faster and produces a better long-term aesthetic outcome than smooth sutures.

Comparing breast-reduction techniques: time-to-event analysis and recommendations.

BACKGROUND: Breast reduction is a common procedure used to improve physical and aesthetic factors associated with breast hypertrophy. This study investigated how surgical technique alone affects the risk factors for complications and profiled differences between techniques. Complications were assessed by the use of time-to-event methods. METHODS: Patient information was extracted from a cohort of 283 patients. Demographic, surgical, and follow-up information was analyzed for patients undergoing surgical procedures using the inferior pedicle Wise pattern (IPWP) and modified Hall-Findlay (MHF) techniques. The patients managed with the IPWP technique were considered control subjects. The failure rates were described using the Kaplan-Meier failure estimator to provide a true estimate of the experienced complication rates. RESULTS: Overall, few differences were noted between the groups except for total tissue removed. The overall failure (complication) rate at 6 months was 18.8%, with 9% of all the patients experiencing a major complication that required operative intervention/revision. As expected, the period with the greatest risk of complication was the first month after surgery. Surgical technique, total tissue removed, and age were nonpredictive of complications. Overall, the IPWP group had significantly more total tissue removed than the MHF group (median difference, 227 g; P=0.002). There was no evidence of a learning curve when an experienced surgeon moved from the one technique to the other. CONCLUSION: At 6 months after surgery, 19% of patients are expected to have experienced a complication. There appears to be few differences in outcomes between the techniques of breast reductions used, and the success or otherwise almost certainly relates to factors independent of surgical technique and includes patient selection, operative skill, and experience. Time-to-event analysis provides a precise assessment and description of the complication profile. LEVEL OF EVIDENCE III: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors at www.springer.com/00266.

Vascularized tissue-engineered chambers promote survival and function of transplanted islets and improve glycemic control.

We have developed a chamber model of islet engraftment that optimizes islet survival by rapidly restoring islet-extracellular matrix relationships and vascularization. Our aim was to assess the ability of syngeneic adult islets seeded into blood vessel-containing chambers to correct streptozotocin-induced diabetes in mice. Approximately 350 syngeneic islets suspended in Matrigel extracellular matrix were inserted into chambers based on either the splenic or groin (epigastric) vascular beds, or, in the standard approach, injected under the renal capsule. Blood glucose was monitored weekly for 7 weeks, and an intraperitoneal glucose tolerance test performed at 6 weeks in the presence of the islet grafts. Relative to untreated diabetic animals, glycemic control significantly improved in all islet transplant groups, strongly correlating with islet counts in the graft (P<0.01), and with best results in the splenic chamber group. Glycemic control deteriorated after chambers were surgically removed at week 8. Immunohistochemistry revealed islets with abundant insulin content in grafts from all groups, but with significantly more islets in splenic chamber grafts than the other treatment groups (P<0.05). It is concluded that hyperglycemia in experimental type 1 diabetes can be effectively treated by islets seeded into a vascularized chamber functioning as a "pancreatic organoid."

Preliminary evaluation of an active end-of-service-life indicator for organic vapor cartridge respirators.

Data are presented on a microwatt chemiresistor microsensor for use with negative-pressure organic vapor respirators. This sensor would operate at or within a sorbent bed and detect parts per million levels of chemical vapors and/or gases as a function of sensor resistance. Sensors were evaluated against four challenge concentrations of ethyl acetate (750 ppm, 1000 ppm, 1500 ppm, and 2000 ppm). Direct comparison of breakthrough times and curves for the chemiresistor microsensor and a standard infrared (IR) detector system were made. The chemiresistor sensor responses were found to correlate well with the IR system. The evaluation showed that although the chemiresistor sensors were not as sensitive as the IR detectors, they could be used if located inside the charcoal bed. Thus, these sensors could function as organic-vapor detectors and could be used in cartridge applications. However, further improvements in stability and sensitivity of these chemiresistor sensors is necessary.